AIDS Epidemic: Is an End Possible?

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NEW YORK CITY — More than 30 years after the discovery of the
AIDS virus, experts are optimistic that a cure for the disease
will be found, and that an end to the AIDS epidemic is possible.

But they caution there is still a lot of work to be done.

Since the first cases of AIDS were reported in 1981, more than
25 million people worldwide have died of AIDS. There are
currently 33 million people living with AIDS, including 1 million
in the United States. There are 50,000 new infections in the
United States each year.

Three methods that are being explored to end the
AIDS epidemic are drugs, vaccines and gene therapy.

There are already drugs that can
prevent AIDS, which is caused by the human immunodeficiency
virus (HIV). Recent research has shown that taking antiretroviral
drugs not only reduces the amount of HIV in the body, it can also
stop transmission of the virus. People at high risk for
contracting HIV can now take a daily pill to prevent infection,
Dr. Robert Grant, an HIV researcher at the Gladstone Institute of
Virology and Immunology, said here Friday (May 31) at a panel at
the World Science Festival.

But others say these drugs will not be enough to stop AIDS
spread.

"We've got to find a way to immunize people, so that they don't
have to take an action to protect themselves," said David
Baltimore, a noble prize winner and professor of biology at the
California Institute of Technology, who also spoke on the panel.
"That's how public health works." [ Watch
the World Science Festival Live ]

In 1984, Margaret Heckler, the Secretary of Health and Human
Services at the time, said that a vaccine against HIV was
expected within two years. But today, no vaccine exists, and most
trials testing HIV vaccines have failed to show any benefit.

The reason making an
HIV vaccine is so difficult is because the virus has already
found a way around the body's defense — it is able to invade
immune cells, the very cells that are supposed to attack it.

But recently, researchers have devised new ways of creating HIV
vaccines.

One method uses stem cells that are engineered to develop into
immune cells that lack the port of entry for the HIV virus.
Without this port, or receptor, HIV can't get inside to thwart
the immune system's attack.

Another approach is to use gene therapy to get the body to make
special immune cells, called broadly neutralizing antibodies,
which are capable of preventing HIV infection. Most people don't
make these antibodies in response to HIV. But the gene therapy
gives cells the genetic material they need to make the
antibodies.

Both the stem cell and gene therapy methods were invented by
Baltimore and colleagues. Baltimore said he hopes to start a
trial for the stem cell therapy next month, and one for the gene
therapy within a year.

Experts point out that even when a trial fails, researchers can
still learn something. "It's only through failure that you get to
success," Grant said.

Peter Staley, an AIDS activist, said he expects a cure within his
lifetime, perhaps within the next 15 years. "Everybody thinks it
can be done, it's just a matter of time and effort," Staley said.